IMAGE CAPTURING APPARATUS AND METHOD OF CONTROLLING THE SAME

摘要

An image capturing apparatus having an image sensor including focus detection pixels capable of outputting a pair of image signals for focus detection determines whether each line of the pixels of the image sensor is an addition/non-addition line that outputs the image signal suitable/unsuitable for detection of a correlation amount, obtains the correlation amount for each addition line based on the pair of image signals, add the obtained correlation amount of the addition line, counts the number of addition lines, obtains a defocus amount based on the added correlation amount, and drives a focus lens based on the defocus amount when a product of an evaluation value representing reliability of the defocus amount and a predetermined standard number of additions is smaller than the product of the number of addition lines and a standard evaluation value representing a predetermined evaluation value.

主权项

1. An image capturing apparatus comprising:
an image sensor including a plurality of pixels that are two-dimensionally arranged and include focus detection pixels including photoelectric conversion units capable of outputting a pair of image signals obtained by receiving a pair of light beams that have passed through different exit pupil regions of an imaging optical system; a determination unit configured to determine whether each line of the pixels of said image sensor is a non-addition line that outputs the image signal unsuitable for detection of a correlation amount; a calculation unit configured to obtain the correlation amount for each addition line based on the pair of image signals output from the focus detection pixel included in the addition line determined not to be the non-addition line by said determination unit and add the obtained correlation amount of the addition line; a counting unit configured to count the number of addition lines added by said calculation unit; a computing unit configured to obtain a defocus amount based on the correlation amount added by said calculation unit; and a focus control unit configured to drive a focus lens included in the imaging optical system based on the defocus amount when a product of an evaluation value representing reliability of the defocus amount obtained by said computing unit and a predetermined standard number of additions is smaller than the product of the number of addition lines counted by said counting unit and a standard evaluation value representing a predetermined evaluation value.